Evolution notes: Part I with Answers

Darwin and Natural selection

  • Who is the father of Evolution?

Charles Darwin

  • As Darwin traveled around the world, what did he notice?

Plants and animals from different parts of the world were different from each other but still shared some similarities. The patterns that he saw suggested that species had changed over time and had given rise to new and different species.

  • Where did Darwin develop many of his ideas about evolution?

Galapagos islands

  • What is Descent with modification?

Each species had descended, with changes, from other species over time.

  • What is the main mechanism by which evolution takes place?

Natural Selection (survival of the fittest): nature selects which traits survive

  • What are the 5 components of natural selection?
  • 1.All species have genetic variation within the species.
  • Nature must have something to choose from.
  • 2.Organisms produce more offspring than can survive….nature must have enough to choose from
  • 3.Since more organisms are produced than can survive, competition exists (struggle for existence)
  • Species compete with others of the same species and with other species.
  • For food, water, shelter, space, mates, etc.
  • Competition affected by short-term natural disasters and by long term environmental changes.
  • 4.Survival of the Fittest: some organisms are more suited to their environment as a result of variations in the species.
  • What is Fitness? The ability to survive and have kids…result of adaptations.
  • Best fit  survive and pass on their genes
  • Less fit  don’t survive and therefore don’t pass on their genes.
  • 5. Descent with modification: Living species today are descended with the modifications from common ancestors that lived in the past.
  • Characteristics (alleles) of most fit increase in a population over time. Less fit characteristics are eventually eliminated from the gene pool.
  • What is an adaptation?

Any inherited characteristic (a gene variation) that can increase an organism’s chance of survival.

  • An organism is either born with the adaptation that enables it to survive or it isn’t and it dies.
  • What did Darwin call his book?

On the origin of species

Published in 1859

  • What are some examples of Natural selection in action?

Camoflauge,mimicry, warning coloration, eye spots, counter shading

  • Things to remember about Evolution:
  • 1.Individuals cannot evolve. Populations (group of same species) evolve.
  • 2. Natural selection is the mechanism of evolution (drives evolution)
  • 3.Evolution occurs by chance (Not goal oriented).
  • 4. Organisms are born with adaptations, they cannot adapt because they need to or want to.